The peak-to-average ratio (“PAR”) of a radio frequency input signal to an amplifier affects the output power from the amplifier, the power efficiency of the amplifier, and the distortion in the output of the amplifier. The peak-to-average ratio of the input signal to an amplifier may vary over time due to the modulation of a carrier according to the input signal. Peaks in the input signal may cause the amplifier to enter saturation with higher peaks causing the amplifier to go further into saturation. The amplifier saturation causes distortion of the amplifier output which affects the frequency spectrum of the output. To help prevent the amplifier from entering saturation, the input signal may be “backed-off” so that the peaks of the input signal do not cause the amplifier to enter saturation. As a result, the average power output from the amplifier is reduced which decreases the output power of the amplifier and decreases the power efficiency of the amplifier. Input signals with low peak-to-average ratios can be amplified with less back-off and can thus produce more output power with a higher power efficiency, and affect the spectrum of the output less than high peak-to-average input signals.